Wang Jiantao, Ge Jian, Sadun A A, Lam T T
Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 51006, China.
Yan Ke Xue Bao. 2004 Mar;20(1):25-9.
To set up the Sharma's chronic intraocular hypertension model and investigate the intraocular pressure (IOP) as well as the optic nerve damage of this model in rat.
The operations of the chronic intraocular hypertension model were performed as described by Sharma in 60 Male Lewis albino rats. IOP was measured using the Tono-Pen XL immediately after surgery and then at 5 day, 2 week or 4 week intervals. Cresyl violet staining of whole-mounted retinas was used to label retinal ganglion cells (RGCs), then RGCs were counted. Paraphenylenediamine (PPD) staining was performed in the semi-thin cross sections of optic nerve of rat, in order to know whether the axons of optic nerve were degenerated or not.
There were 47 rats with higher IOP after the episcleral veins cauterized in 60 rats. The ratio of elevated IOP was 78.3%. The IOPs were stable in 4 weeks. After cresyl violet staining, the RGCs loss was 11.0% and 11.3% was found in the central and peripheral retina respectively after 2 weeks of increased IOP. After 4 weeks of increased IOP, the loss of RGCs was 17% for the central retina and 24.6% for the peripheral retina. In the retinas without higher IOP, there was no loss of RGCs. PPD staining showed that optic nerve of rat with about 5.3% damage of axons located at the superior temporal region. Region of affected optic nerve 1 mm posterior to the globe by light microscope showed evidence of damaged axons with axonal swelling and myelin debris.
Sharma's chronic intraocular hypertension model is a reproducible and effective glaucoma model, which mimics human glaucoma with chronically elevation IOP and induced RGCs loss and damage of optic nerve.
建立夏尔马慢性高眼压模型，并研究该模型大鼠的眼压以及视神经损伤情况。
按照夏尔马所述方法，对60只雄性刘易斯白化大鼠进行慢性高眼压模型手术。术后立即使用Tono-Pen XL测量眼压，随后每隔5天、2周或4周测量一次。用甲酚紫对全视网膜进行染色以标记视网膜神经节细胞（RGCs），然后对RGCs进行计数。对大鼠视神经半薄切片进行对苯二胺（PPD）染色，以了解视神经轴突是否发生退变。
60只大鼠巩膜静脉烧灼术后有47只眼压升高，眼压升高比例为78.3%。眼压在4周内保持稳定。甲酚紫染色后，眼压升高2周后，中央视网膜和周边视网膜的RGCs损失分别为11.0%和11.3%。眼压升高4周后，中央视网膜RGCs损失为17%，周边视网膜为24.6%。在眼压未升高的视网膜中，RGCs没有损失。PPD染色显示，大鼠视神经颞上区域约有5.3%的轴突损伤。光镜下观察眼球后1 mm处的视神经区域，可见受损轴突，表现为轴突肿胀和髓鞘碎片。
夏尔马慢性高眼压模型是一种可重复且有效的青光眼模型，它通过慢性眼压升高模拟人类青光眼，并导致RGCs损失和视神经损伤。
